This application claims the priority of German Application No. 196 12 062.4, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a display unit for data dependent on the energy consumption of a vehicle.
From German Patent Document DE-PS 30 46 076, a fuel display unit is known which has devices for measuring, analyzing and displaying the instantaneous fuel consumption and the resulting data. The following is specifically indicated: the tank limit in the case of the instantaneous driving condition on the basis of constant circumstances in the form of a display of figures; the fuel quantity contained in the fuel tank in the form of figures; the flashing of a colored light when a minimum quantity of fuel is reached; and the display of the instantaneous fuel consumption by lights of three different colors, in which case the lights indicate during the flashing whether the fuel consumption is within, below or above a predetermined range. In the case of this tank limit display, it is a disadvantage that the indicated numbers change constantly because of changing driving conditions and thus may irritate the driver and divert his attention. It is another disadvantage that these so-called vehicle computers, as a rule, are offered only in the case of higher-priced vehicles or as optional equipment.
It is an object of the invention to provide a display unit for data dependent on a vehicle's energy consumption which, in a clear manner, displays the most important data dependent on the energy consumption and the contents of the energy storage device.
This and other objects have been achieved according to the present invention by providing a display unit for data dependent on energy consumption of a vehicle, the vehicle having at least one motor and at least one storage system which can be filled with energy, having devices for determining a remaining amount of energy instantaneously situated in said storage system and consumption parameters of the vehicle, and having devices for calculating a driving distance which can be reached with said remaining amount of energy and said consumption parameters, wherein, as a function of said amount of remaining energy in the storage system and as a function of said consumption parameters, the display unit displays a range of said driving distances which is obtained from a minimal and a maximal average consumption of the motor.
This and other objects have also been achieved according to the present invention by providing a system for displaying an expected range of driving distances for a vehicle having a driving unit and an energy storage unit, comprising a sensor which senses an amount of remaining energy in said energy storage unit; means for determining an average minimum energy consumption rate and an average maximum energy consumption rate of said driving unit; means for calculating a minimum expected driving distance based on said sensed amount of remaining energy and said average maximum energy consumption rate; means for calculating a maximum expected driving distance based on said sensed amount of remaining energy and said average minimum energy consumption rate; means for displaying said expected range of driving distances defined by said minimum expected driving distance and said maximum expected driving distance.
This and other objects have also been achieved according to the present invention by providing a method of displaying an expected range of driving distances for a vehicle having a driving unit and an energy storage unit, comprising sensing an amount of remaining energy in said energy storage unit; determining an average minimum energy consumption rate and an average maximum energy consumption rate of said driving unit; calculating a minimum expected driving distance based on said sensed amount of remaining energy and said average maximum energy consumption rate; calculating a maximum expected driving distance based on said sensed amount of remaining energy and said average minimum energy consumption rate; displaying said expected range of driving distances defined by said minimum expected driving distance and said maximum expected driving distance.
The display unit according to the invention has a driving distance display which indicates to the driver a range of driving distance still to be expected, for example, in kilometers. In a first embodiment of a display unit, this driving distance range is obtained as a function of the amount of energy instantaneously situated in the energy storage system and the minimal and maximal average consumption of the vehicle engine in conjunction with the vehicle-specific parameters.
In a second embodiment of a display unit according to the invention, in the case of the indicated driving distance range, the driver-specific characteristics are also taken into account. These driver-specific characteristics may, for example, be sporty or economical driving methods. For example, from an empirically determined range of an average consumption, which covers a predetermined percentage, for example, between 50-75%, of a driver's vehicle handling, the driving distance range is limited resulting from the vehicle-specific average consumption. A further limitation of this resulting driving distance range is achieved in that, over a certain time period, the vehicle handling is measured and analyzed of a driver fixedly assigned to the vehicle. From these data, a minimal and maximal average consumption is determined and is used for calculating the driving distance range. The indicated driving distance range will then become even narrower.
In the case of both embodiments, it is advantageous that, because of the display of the driving distance range of the vehicle, the indication of the instantaneous energy amount in the storage system or in the energy tank can be eliminated and the driver knows directly from the indicated driving distance range how far he can expect to still drive with the still existing stored energy as a function of the vehicle's consumption and under various operating conditions.
It is another advantage that a display of driving distance range jumps in the case of a changed driving method or changed driving conditions is eliminated because the indication of a range contains these variable parameters. If a vehicle is, for example, driven by different drivers, as occurs in the case of a rented car, the respective driver can immediately see which driving distance can still be maximally expected without knowing the consumption of the engine and the total content of the fuel tank.
In an advantageous embodiment, the display of the minimal or maximal driving distance takes place by means of an indicator instrument with two arms which can be controlled independently of one another. In another advantageous embodiment, the display of the driving distance range takes place by way of a bar display with a highlighted area, in which case the highlighting can take place in color and/or in an illuminated manner. In a third advantageous embodiment, the indication of the driving distance range takes place by way of a digital display in the form of mutually spaced numbers.
In an advantageous embodiment, the driving distance scale is divided in an enlarged manner starting from the range of the reserve quantity so that the driver can more precisely estimate the possible driving distance. It is also advantageous for the range scale in the upper range, in which a relatively large amount of energy is still contained in the energy tank, to have a smaller or narrower graduation. The energy reserve quantity can be displayed in that the display color is changed. As a result, a separate reserve light can be eliminated.
In an advantageous embodiment, the driving distance to be expected with the instantaneous or current driving method is visually displayed within the highlighted or displayed driving distance range.
Another advantageous embodiment of the display unit is characterized in that the indicated driving distance range is limited or shortened by a constant or variable percentage. In a space-saving embodiment, the upper range of the driving distance scale is cut off, which in particular relates to the driving distance in the case of a particularly economical driving method; that is, the maximal driving distance starts with an average or median value.
It is advantageous that, in the case of the display unit according to the invention, the limit values of the average consumptions used as the basis can be varied automatically by way of a corresponding software during the driving operation. If the analysis device of the display unit according to the invention determines that there is an exceeding of or falling below the empirically determined limit values, the limited driving distance range is expanded and adapted to these limit values.
In a further embodiment, in addition to the driving distance range, the amount of energy instantaneously contained in the energy tank is also displayed or can be queried.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.